Updated readme and dev instructions

README.md

@@ -7,6 +7,8 @@ yarn install
 
 ### Compiles and hot-reloads for development
 ```
+VUE_APP_RETRIBUTE_API_URL=http://localhost:8000/ yarn run serve
+# or leave empty to use the production API
 yarn run serve
 ```
 

src/config.js

 export default {
-	RetributeAPIUrl: process.env.RETRIBUTE_API_URL || 'https://api.retribute.me/'
+	RetributeAPIUrl: process.env.VUE_APP_RETRIBUTE_API_URL || 'https://api.retribute.me/'
 }